The fourth generation of the Infiniti G, known as the V36, debuted for the 2007 model year. Based on the Nissan Skyline, the V36 Infiniti G continued to be built in Sedan and Coupe body styles like the previous V35 generation, but from the 2009 model year, a Convertible was available. Over the course of production, three main variants were offered, the G25, G35, and G37, each named for this displacement of its V6 engine (2.5L, 3.5L, and 3.7L, respetively). Initially, these cars were available with a 5 speed automatic transmission, but after 2008, a 7 speed automatic was used. As well as the automatic transmission, a 6 speed manual was available throughout production. After 2013, the final year of production, the sedan version of the Infiniti G was known as the Q40, while coupes and convertibles retained their name. Infiniti replaced the sedan (Q40) with the Q50, while coupes and convertibles were replaced by the Q60.